Condensing the 700-page report of the United Nations Intergovernmental Panel on Climate Change (IPCC) into a 20-page summary requires selectivity, says Kenneth Green of the Reason Public Policy Institute who was an expert reviewer for the Working Group I and Working Group II volumes of the IPCC Third Assessment Report.
As with past summaries for policy-makers, the summary tends to downplay uncertainty, emphasise human culpability and generally provide only information supporting policy options favoured by the United Nations the immediate adoption of international agreements to reduce the emissions of “greenhouse gases.”
The new “Summary for Policy-Makers” suggests a higher range of potential warming by 2100 and a higher sea-level rise than previous summaries. Global average temperature in the new report is estimated to increase from a low of 1.4° centigrade to a high of 5.8° (2.5° to 10.4° Fahrenheit) by 2100.
Predicted sea-level increases under the new scenarios range from 9 to 88 centimetres (4 inches to 3 feet) by 2100.
Among other points, critics say the clear difference between ground-level temperature readings (which are increasing) and high-altitude readings from balloons and satellites (which are unchanging) reveals a critical weakness of the climate models used to predict future impacts of global warming.
Source: Kenneth Green (Chief Scientist, Reason Public Policy Institute), Science vs. Spin: Government Warming Redux, Brief Analysis No. 378, November 12, 2001, NCPA.
For text http://www.ncpa.org/pub/ba/ba378/
For more on Global Warming http://www.ncpa.org/iss/env/
FMF Policy Bulletin\20 November 2001
